Venturi drying exhaust duct

ABSTRACT

An exhaust duct includes a nozzle duct and a cone duct. The nozzle duct includes a first wall forming a first aperture and including a reducing section and an expanding section. The reducing section includes a first edge and a second edge. The expanding section is mounted to the reducing section and includes a third edge and a fourth edge. The reducing section has a circumference that decreases from the first edge to the second edge. The second edge is mounted to the third edge of the expanding section. The expanding section has a circumference that increases from the third edge to the fourth edge. The cone duct includes a second wall forming a second aperture. The nozzle duct is mounted within the second aperture. An air gap is provided between an interior of the second wall and an exterior of the nozzle duct.

BACKGROUND

Dishwashers are provided with an interior wash chamber or tub into whichone or more racks or baskets are designed to hold dishware within theinterior of the tub during operation of the dishwasher to wash thedishware. Dishwashers include a drying cycle after the washing cyclethat expels hot humid drying air. The prevention of condensation onouter door panels, cabinet panels, and floors is an importantconsideration when designing the exhaust system so that the surroundingelements are not damaged.

SUMMARY

In an example embodiment, an exhaust duct is provided. The exhaust ductincludes, but is not limited to, a nozzle duct and a cone duct. Thenozzle duct includes, but is not limited to, a first wall that forms afirst aperture. The first wall includes, but is not limited to, areducing section and an expanding section. The reducing sectionincludes, but is not limited to, a first edge and a second edge oppositethe first edge. The expanding section is mounted to the reducing sectionand includes, but is not limited to, a third edge and a fourth edgeopposite the third edge. The reducing section has a circumference thatdecreases from the first edge to the second edge. The second edge ismounted to the third edge of the expanding section. The expandingsection has a circumference that increases from the third edge to thefourth edge. The cone duct includes, but is not limited to, a secondwall that forms a second aperture. The nozzle duct is mounted within atleast a portion of the second aperture. An air gap is provided betweenat least a portion of an interior of the second wall and at least aportion of an exterior of the nozzle duct to allow air to enter thesecond aperture.

In another example embodiment, an exhaust system for a dishwasher isprovided. The exhaust system includes, but is not limited to, an exhaustblower and the exhaust duct. The exhaust blower includes, but is notlimited to, an exhaust channel and an exhaust fan mounted within theexhaust channel to move received air into the exhaust channel when theexhaust fan is on. The exhaust duct is mounted to the exhaust channel.

In yet another example embodiment, a dishwasher is provided. Thedishwasher includes, but is not limited to, a body, a conduit system,and an exhaust system. The conduit system is configured to providewashing fluid to an interior of the body. The exhaust system is mountedto the body. The exhaust system includes, but is not limited to, anintake conduit connected to receive air from the interior of the bodyduring a drying cycle of the dishwasher, an exhaust blower, and theexhaust duct. The exhaust blower includes, but is not limited to, anexhaust channel, and an exhaust fan mounted within the exhaust channelto receive the air received into the intake conduit and to move thereceived air into the exhaust channel when the exhaust fan is on. Theexhaust duct is mounted to the exhaust channel.

Other principal features of the disclosed subject matter will becomeapparent to those skilled in the art upon review of the followingdrawings, the detailed description, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

Illustrative embodiments of the disclosed subject matter will hereafterbe described with reference to the accompanying drawings, wherein likenumerals denote like elements.

FIG. 1 depicts a front perspective view of a dishwasher in accordancewith an illustrative embodiment.

FIG. 2 depicts a front perspective view of the dishwasher of FIG. 1without a door or dishware racks in accordance with an illustrativeembodiment.

FIG. 3A depicts a front view of the dishwasher tub of the dishwasher ofFIG. 1 in accordance with an illustrative embodiment.

FIG. 3B depicts a zoomed front perspective view of a bottom of thedishwasher of FIG. 1 without the door and a kickplate in accordance withan illustrative embodiment.

FIG. 3C depicts a zoomed right-side perspective view of the bottom ofthe dishwasher of FIG. 1 with portions of an exhaust system removed inaccordance with an illustrative embodiment.

FIG. 4A depicts a front view of the exhaust system of the dishwasher ofFIG. 1 in accordance with an illustrative embodiment.

FIG. 4B depicts a front view of the exhaust system of FIG. 4A with anouter exhaust wall removed in accordance with an illustrativeembodiment.

FIG. 4C depicts a left perspective view of the exhaust system of FIG. 4Bin accordance with an illustrative embodiment.

FIG. 4D depicts a top, back perspective view of the exhaust system ofFIG. 4B in accordance with an illustrative embodiment.

FIG. 4E depicts a right-side, back perspective view of the exhaustsystem of FIG. 4B in accordance with an illustrative embodiment.

FIG. 4F depicts a bottom, back perspective view of the exhaust system ofFIG. 4B in accordance with an illustrative embodiment.

FIG. 5A depicts a front perspective view of an exhaust blower of theexhaust system of FIG. 4D in accordance with an illustrative embodiment.

FIG. 5B depicts a front perspective view of the exhaust blower of FIG.5A with a blower cover plate removed in accordance with an illustrativeembodiment.

FIG. 5C depicts a front perspective view of the exhaust blower of FIG.5A with a blower motor removed in accordance with an illustrativeembodiment.

FIG. 5D depicts a back perspective view of the exhaust blower of FIG. 5Ain accordance with an illustrative embodiment.

FIG. 5E depicts a right-side, back perspective view of the exhaustblower of FIG. 5A in accordance with an illustrative embodiment.

FIG. 6 depicts a front perspective view of the exhaust blower body ofFIG. 5A in accordance with an illustrative embodiment.

FIG. 7A depicts a front perspective view of an exhaust duct of theexhaust blower of FIG. 5A in accordance with an illustrative embodiment.

FIG. 7B depicts a back perspective view of the exhaust duct of FIG. 7Ain accordance with an illustrative embodiment.

FIG. 7C depicts a left-side perspective view of the exhaust duct of FIG.7A in accordance with an illustrative embodiment.

FIG. 7D depicts a second left-side perspective view of the exhaust ductof FIG. 7A in accordance with an illustrative embodiment.

FIG. 8A depicts a front perspective view of a nozzle duct of the exhaustduct of FIG. 7A in accordance with an illustrative embodiment.

FIG. 8B depicts a top perspective view of the nozzle duct of FIG. 8A inaccordance with an illustrative embodiment.

FIG. 9A depicts a back cross-sectional view of the exhaust duct of FIG.7A in accordance with an illustrative embodiment.

FIG. 9B depicts a left cross-sectional view of the exhaust duct of FIG.7A in accordance with an illustrative embodiment.

FIG. 9C depicts a second left cross-sectional view of the exhaust ductof FIG. 7A in accordance with an illustrative embodiment.

FIG. 10 depicts a back cross-sectional view of the nozzle duct of FIG. 8in accordance with an illustrative embodiment.

FIG. 11 depicts a back cross-sectional view of a cone duct of theexhaust duct of FIG. 7A in accordance with an illustrative embodiment.

FIG. 12 shows an air flow velocity through the exhaust duct of FIG. 7Ain accordance with an illustrative embodiment.

FIG. 13 shows a water vapor fraction in the exhaust duct of FIG. 7A inaccordance with an illustrative embodiment.

DETAILED DESCRIPTION

Referring to FIG. 1 , a dishwasher 100 is shown in accordance with anillustrative embodiment. Dishwasher 100 may include a door 102 and abody 104. In the illustrative embodiment, body 104 includes a pluralityof walls that, in combination with door 102, form an enclosed space orwash tub 200 (shown with reference to FIG. 2 ). The plurality of wallsof body 104 may include a top wall 106, a right-side wall 108, aleft-side wall 110, a back wall 112, and a bottom wall 114. Top wall106, right-side wall 108, left-side wall 110, back wall 112, and a tubbottom wall 202 (shown with reference to FIG. 2 ) define wash tub 200.Bottom wall 114 may not cover the entire area between right-side wall108, left-side wall 110, and back wall 112. A wall may include aplurality of walls such as an interior wall that is distinct from anexterior wall but together provide a barrier between wash tub 200 andthe exterior of dishwasher 100. Items such as insulation, wires, piping,electronics, one or more pumps, a heating element, etc. may be mountedwithin one or more of the walls. A kickplate 132 may be positioned neara bottom edge of door 102 to hide the items mounted below tub bottomwall 202 from view.

Door 102 rotates from a vertical position to a horizontal position asunderstood by a person of skill in the art though door 102 may rotate inother directions in alternative embodiments. A plurality of hinges suchas a right hinge 122 pivotally mount door 102 to body 104 proximate alower edge of door 102. In the illustrative embodiment, door 102 rotatesdownward to provide access to wash tub 200. In an alternativeembodiment, dishwasher 100 may be implemented as a drawer typedishwasher in which door 102 slides out from body 104.

Wash tub 200 may include one or more racks on which dishware or otheritems are placed for washing and/or rinsing. For example, dishwasher 100includes a top dishware rack 116 and a bottom dishware rack 118.Dishwasher 100 may include one or more additional racks above and/orbelow top dishware rack 116 and/or bottom dishware rack 118. Forexample, a third rack 312 (shown referring to FIG. 3A) may be positionedabove top dishware rack 116. As understood by a person of skill in theart, top dishware rack 116, bottom dishware rack 118 and third rack 312may be slid into and out of wash tub 200 using a variety of mountingmethods. A height of top dishware rack 116 and/or bottom dishware rack118 within body 104 and relative to tub bottom wall 202 may beadjustable.

Wash tub 200 may include one or more spray arms that spray a washingfluid on the dishware loaded on the one or more racks. For example,dishwasher 100 may include a lower spray arm 204, an upper spray arm 300(shown referring to FIG. 3A), and a middle spray arm 302 (shownreferring to FIG. 3A) mounted at different heights above tub bottom wall202. A top spray arm conduit 120 may mount upper spray arm 300 to a washpump 304 (shown with reference to FIG. 3A). Upper spray arm 300 may bemounted to extend down from an inner surface of top wall 106 and may beconfigured to spray the washing fluid upward and/or downward asunderstood by a person of skill in the art. Lower spray arm 204 may bemounted to extend up from tub bottom wall 202 and may be configured tospray the washing fluid upward and/or downward as understood by a personof skill in the art. Middle spray arm 302 may be mounted to a bottom oftop dishware rack 116 and may be configured to spray the washing fluidupward and/or downward as understood by a person of skill in the art.Though not shown, various conduits may connect wash pump 304 to lowerspray arm 204 and to middle spray arm 302. For example, a middle sprayarm nozzle 206 (shown with reference to FIG. 2 ) may provide fluid fromwash pump 304 to middle spray arm 302. Dishwasher 100 may include afewer or a greater number of spray arms.

Dishwasher 100 further may include an exhaust system 124 that processeshot humid air used as part of a drying cycle of dishwasher 100 beforereleasing the air exterior of dishwasher 100. In the illustrativeembodiment, exhaust system 124 is mounted to top wall 106, to right-sidewall 108, and between bottom wall 114 and tub bottom wall 202. Inalternative embodiments, exhaust system 124 can be mounted to otherwalls of dishwasher 100. Exhaust system 124 may include air intake head126, an intake conduit 130, an outer exhaust wall 128, an inner exhaustwall 402 (shown referring to FIG. 4B), a track 404 (shown referring toFIG. 4B), a drain 406 (shown referring to FIG. 4B), a first air intakeaperture wall 408 (shown referring to FIG. 4B), a second air intakeaperture wall 410 (shown referring to FIG. 4B), an ambient air track 412(shown referring to FIG. 4B), a blower fan 318 (shown referring to FIG.3C) of an exhaust blower 416 (shown referring to FIG. 4C), and anexhaust duct 314 (shown referring to FIG. 3A).

Use of directional terms, such as top, bottom, right, left, front, back,upper, lower, etc. are merely intended to facilitate reference to thevarious surfaces of the described structures relative to theorientations shown in the drawings and are not intended to be limitingin any manner. For example, when referring to the dishwasher, front iswith reference to a front of dishwasher 100 as defined by a location ofdoor 102.

As used in this disclosure, the term “mount” is intended to define astructural connection between two or more elements and includes mold,join, unite, connect, couple, associate, insert, hang, hold, affix,attach, fasten, bind, paste, secure, bolt, screw, rivet, solder, weld,glue, adhere, form over, layer, and other similar terms. The phrases“mounted on” and “mounted to” include any interior or exterior portionof the elements referenced. These phrases also encompass direct mounting(in which the referenced elements are in direct contact) and indirectmounting (in which the referenced elements are not in direct contact).Elements referenced as mounted to each other herein may further beintegrally formed together, for example, using a molding process asunderstood by a person of skill in the art. As a result, elementsdescribed herein as being mounted to each other need not be discretestructural elements. The elements may be mounted permanently, removably,or releasably to each other unless specified otherwise.

Dishwasher 100 may include a greater or a fewer number of componentsthan those illustrated. The one or more components of dishwasher 100 maybe formed of one or more materials, such as various metals, glass,elastomeric material, and/or plastics having a sufficient strength,rigidity, and/or flexibility to support the described application.

Referring to FIG. 2 , a front view of dishwasher 100 is shown inaccordance with an illustrative embodiment without door 102, topdishware rack 116, and bottom dishware rack 118. Tub bottom wall 202 ismounted within body 104 between right-side wall 108, left-side wall 110,and back wall 112 and above bottom wall 114. A sump screen 206 ismounted to tub bottom wall 202 above a sump 310 (shown with reference toFIG. 3A) and is configured to allow fluid to flow downward out of washtub 200.

Referring to FIG. 3A, a front view of body 104 of dishwasher 100 isshown in accordance with an illustrative embodiment. Referring to FIG.3B, a zoomed front perspective view is shown of a bottom of dishwasher100 without door 102 and kickplate 132 in accordance with anillustrative embodiment. Referring to FIG. 3C, a zoomed right-sideperspective view is shown of the bottom of dishwasher 100 with outerexhaust wall 128 and inner exhaust wall 402 of exhaust system 124removed in accordance with an illustrative embodiment.

In the illustrative embodiment, top dishware rack 116 can be slid in andout of dishwasher 100 using a right-side rail 306 mounted to an interiorof right-side wall 108 and a left-side rail 308 mounted to an interiorof left-side wall 110. Additionally, a height of top dishware rack 116within body 104 and relative to tub bottom wall 202 is adjustable. Thus,top dishware rack 116 may be moved up and down along back wall 112 withmiddle spray arm nozzle 206. As understood by a person of skill in theart, the fluid that is sprayed out of lower spray arm 204, upper sprayarm 300, and/or middle spray arm 302 may be collected in sump 310 thatforms a reservoir at a bottom of tub bottom wall 202 and, if desired,may be filtered and recirculated by a fluid supply system using pump304. Controls for selection of and operation of a cleaning cycle may bemounted to or within door 102 and/or distributed in other locations ofdishwasher 100. Top dishware rack 116, bottom dishware rack 118, andthird rack 312 may be moved in and out of body 104 relative to wash tub200 using a variety of structural sliding mechanisms such as wheels,brackets, rails, etc.

Referring to FIG. 4A, a front view of exhaust system 124 is shown inaccordance with an illustrative embodiment. In the illustrativeembodiment, exhaust system 124 is mounted to right-side wall 108. Forsimplicity, when referring to exhaust system 124, front is withreference to an exterior of right-side wall 108. Referring to FIG. 4B, afront view of exhaust system 124 with outer exhaust wall 128 removed isshown in accordance with an illustrative embodiment. Referring to FIG.4C, a left perspective view of exhaust system 124 with outer exhaustwall 128 removed is shown in accordance with an illustrative embodiment.Referring to FIG. 4D, a top, back perspective view of exhaust system 124is shown in accordance with an illustrative embodiment. Referring toFIG. 4E, a right-side, back perspective view of exhaust system 124 isshown in accordance with an illustrative embodiment. Referring to FIG.4F, a bottom, back perspective view of exhaust system 124 is shown inaccordance with an illustrative embodiment.

Outer exhaust wall 128 and inner exhaust wall 402 are mounted to eachother to form a sealed space there between. Outer exhaust wall 128 andinner exhaust wall 402 are further mounted to right-side wall 108 in theillustrative embodiment. For example, various fasteners may be used tomount outer exhaust wall 128 to inner exhaust wall 402. Air intake head126 is mounted through top wall 106 to receive drying air from withinwash tub 200 that is generated when a drying cycle is entered undercontrol of a controller (not shown) of dishwasher 100.

Intake conduit 130 is mounted between air intake head 126 and the sealedspace defined between outer exhaust wall 128 and inner exhaust wall 402so that the drying air received through air intake head 126 is receivedinto the sealed space. Track 404 defines walls formed between outerexhaust wall 128 and inner exhaust wall 402 to guide the flow of thereceived air within the sealed space including any liquid that isformed. Track 404 is shaped to guide the flow of any liquid that isformed to drain 406 and to guide the flow of the received air to ablower aperture wall 400.

Blower aperture wall 400 is formed through inner exhaust wall 402 andaligned with blower fan 318 so that the drying air received into thesealed space is received into blower fan 318 of exhaust blower 416. Asecond blower aperture wall 316 (shown referring to FIG. 3 ) is formedthrough right-side wall 108 and also aligned with blower fan 318 so thatthe drying air received into the sealed space is received into blowerfan 318 of exhaust blower 416 through right-side wall 108.

First air intake aperture wall 408 and second air intake aperture wall410 are formed through inner exhaust wall 402. First air intake aperturewall 408 is formed within a portion of track 404 above blower aperturewall 400 to allow first ambient air to enter exhaust system 124 beforeentry into blower fan 318 of exhaust blower 416. Second air intakeaperture wall 410 is formed within ambient air track 412 to allow secondambient air to enter exhaust system 124 before entry into blower fan 318of exhaust blower 416. First air intake aperture wall 408 and/or secondair intake aperture wall 410 provide a source of ambient air that can bereceived into the sealed space between outer exhaust wall 128 and innerexhaust wall 402 to reduce a humidity level of the drying exhaust airbefore entry into exhaust blower 416.

In the illustrative embodiment, exhaust blower 416 is mounted to innerexhaust wall 402 interior of right-side wall 108 below tub bottom wall202 and above bottom wall 114. In the illustrative embodiment, exhaustblower 416 is mounted to inner exhaust wall 402 using fasteners 418inserted within standoffs 420. Again, blower fan 318 of exhaust blower416 is aligned with blower aperture wall 400 that is formed throughinner exhaust wall 402 adjacent a lower edge of inner exhaust wall 402so that the air flows downward from air intake head 126 through thesealed space and into blower fan 318 of exhaust blower 416.

Referring to FIG. 5A, a front perspective view of exhaust blower 416 ofexhaust system 124 is shown in accordance with an illustrativeembodiment. For simplicity, when referring to exhaust blower 416, frontis with reference to an interior of right-side wall 108. Referring toFIG. 5B, a front perspective view of exhaust blower 416 with a blowercover plate 500 removed is shown in accordance with an illustrativeembodiment. Referring to FIG. 5C, a front perspective view of exhaustblower 416 with a blower motor housing 504 removed is shown inaccordance with an illustrative embodiment. Referring to FIG. 5D, a backperspective view of exhaust blower 416 is shown in accordance with anillustrative embodiment. Referring to FIG. 5E, a right-side, backperspective view of exhaust blower 416 is shown in accordance with anillustrative embodiment.

Exhaust blower 416 may include blower fan 318, blower cover plate 500,an exhaust blower body 502, and blower motor housing 504. Blower coverplate 500 is mounted to exhaust blower body 502. In the illustrativeembodiment, blower cover plate 500 is mounted to exhaust blower body 502using a snap-hook feature though other mounting devices and/or methodsmay be used in alternative embodiments. A pair of mounting bars 510extend from blower cover plate 500. A corresponding pair of mountinghooks 512 extend from exhaust blower body 502. When blower cover plate500 is mounted to exhaust blower body 502, the pair of mounting hooks512 are inserted within a respective mounting bar of the pair ofmounting bars 510.

Blower cover plate 500 and exhaust blower body 502 form an enclosedspace within which the drying air received into blower fan 318 from thesealed space is routed to exhaust duct 314 under control of blower fan318 that is operated by a motor (not shown) housed within blower motorhousing 504. A shaft 320 (shown referring to FIG. 3C) is mounted to themotor and rotated by operation of the motor when the controller of thedishwasher turns blower fan 318 on as part of the drying cycle.

Blower fan 318 includes a plurality of fan blades 516 distributedcircumferentially around a fan body 514. Fan body 514 is mounted torotate with shaft 320 thereby rotating the plurality of fan blades 516to direct the air received into blower fan 318 circumferentially withinexhaust blower body 502 toward exhaust duct 314.

Exhaust blower body 502 includes a bottom wall 520, an outer sidewall522, a fan aperture wall 524, the pair of mounting hooks 512 that extendoutward from outer sidewall 522, a first channel wall 600 (shownreferring to FIG. 6 ), and a second channel wall 602 (shown referring toFIG. 6 ). Referring to FIG. 6 , a front perspective view of exhaustblower body 502 is shown in accordance with an illustrative embodiment.Fan aperture wall 524 is formed through bottom wall 520 and is sized andshaped to accommodate fan body 514. Outer sidewall 522 is mounted toextend approximately perpendicularly from an outer edge of bottom wall520 to define a channel. The channel surrounds fan body 514 and theplurality of fan blades 516 and is bounded by outer sidewall 522. Outersidewall 522 includes a circular portion and a straight portion. Thestraight portion of outer sidewall 522 includes a first exit channelwall 600 and a second exit channel wall 602. Blower cover plate 500 hasa similar shape to mount to outer sidewall 522 and form the enclosedspace.

Rotation of the plurality of fan blades 516 pulls the air from thesealed space into blower fan 318 around the channel defined by outersidewall 522 and into exhaust duct 314. Exhaust duct 314 may include anozzle duct 506 and a cone duct 508. Nozzle duct 506 is mounted to firstexit channel wall 600 and second exit channel wall 602 and thecorresponding portions of blower cover plate 500 and bottom wall 520 toreceive the air received into the enclosed space through blower fan 318.

Referring to FIG. 7A, a front perspective view of exhaust duct 314 isshown in accordance with an illustrative embodiment. Referring to FIG.7B, a back perspective view of exhaust duct 314 is shown in accordancewith an illustrative embodiment. Referring to FIG. 7C, a left-sideperspective view of exhaust duct 314 is shown in accordance with anillustrative embodiment. Referring to FIG. 7D, a second left-sideperspective view of exhaust duct 314 is shown in accordance with anillustrative embodiment.

Cone duct 508 may include a cone section 712, a center section 714, anda spout section 716 that form a first duct wall that forms a first ductaperture that mounts to nozzle duct 506 to form a continuous duct. Thefirst duct aperture varies in shape and circumference lengthwise withinthe first duct aperture. Cone section 712, center section 714, and spoutsection 716 may form a single wall, for example, using a molding processthough cone duct 508 may include a fewer or a greater number of sectionsand may be formed using one or more distinct parts. For illustration,cone duct 508 may be formed of a plastic material though other materialsmay be used in alternative embodiments.

Center section 714 extends between cone section 712 and spout section716. Cone section 712 has a funnel shape that decreases in circumferencetoward center section 714. The funnel shape of cone section 712 may havelinear or curved walls. Center section 714 has a funnel shape thatincreases in circumference toward spout section 716. The funnel shape ofcenter section 714 may have linear or curved walls. Center section 714has a circular cross-section where it joins with cone section 712 and asquare cross-section where it joins with spout section 716 to provide atransition wall section between cone section 712 and spout section 716.Spout section 716 forms a spout in a lengthwise direction with a bottomwall 726 that extends further from center section 714 than a top wall728 of spout section 716 when viewed from the front or the back. Inalternative embodiments, cone section 712, center section 714, and spoutsection 716 may have different cross-sectional shapes includingcircular, elliptical, or other polygons.

A plurality of fin slits 718 are formed in an edge of cone section 712to extend toward center section 714. In the illustrative embodiment, theplurality of fin slits 718 includes two slits located at 180-degreeintervals around cone section 712. When a longer edge of spout section716 is down, the plurality of fin slits 718 are located on a front and aback of cone section 712.

A plurality of snap fit slits 720 is formed in an edge of cone section712 to extend toward center section 714. In the illustrative embodiment,the plurality of snap fit slits 720 includes two slits located at180-degree intervals around cone section 712. When a longer edge ofspout section 716 is down, the plurality of snap fit slits 720 arelocated on a top and a bottom of cone section 712 so that they areseparated from the plurality of fin slits 718 by 90-degrees. Each snapfit slit of the plurality of snap fit slits 720 is aligned with arespective snap aperture wall of a plurality of snap aperture walls 722to extend toward center section 714. Each snap aperture wall of aplurality of snap aperture walls 722 is formed through a portion of conesection 712.

A plurality of blades 724 extend outward and lengthwise between conesection 712 and center section 714. A blade of the plurality of blades724 is aligned with either a fin slit of the plurality of fin slits 718or a snap fit slit of the plurality of snap fit slits 720 such thatthere are four blades separated from each other by 90-degrees thoughthis is not required. In alternative embodiments, cone duct 508 mayinclude a greater or a fewer number of the plurality of fin slits 718,of the plurality of snap fit slits 720, of the plurality of snapaperture walls 722, and/or of the plurality of blades 724. For example,the plurality of blades 724 may be included to stiffen cone duct 508 ifcone duct 508 is formed using blow molding. If cone duct 508 is formedusing injection molding, the plurality of blades 724 may not beincluded.

Nozzle duct 506 may include a mounting head section 700, a tapered bodysection 702, a reducing body section 704, and an expanding body section800 (shown referring to FIG. 8 ) that form a second duct wall that formsa second duct aperture. The second duct aperture varies in shape andcircumference lengthwise and in some cases circumferentially. The secondduct wall of nozzle duct 506 is shaped to create a venturi effect on theair received into exhaust duct 314 from the channel. The venturi effectcreates a low-pressure zone by reducing a cross-section along theexhaust air flow path and then expanding the cross-section.

Referring to FIG. 8A, a front perspective view of nozzle duct 506 isshown in accordance with an illustrative embodiment. Referring to FIG.8B, a top perspective view of nozzle duct 506 is shown in accordancewith an illustrative embodiment. Mounting head section 700, tapered bodysection 702, reducing body section 704, and expanding body section 800form a single wall. Mounting head section 700, tapered body section 702,reducing body section 704, and expanding body section 800 may be formed,for example, using a molding process though nozzle duct 506 may includea fewer or a greater number of sections and may be formed using one ormore distinct parts. For illustration, nozzle duct 506 may be formed ofa plastic material though other materials may be used in alternativeembodiments.

Mounting head section 700 is mounted to exhaust blower 416 to receivethe air from the enclosed space that surrounds blower fan 318. In theillustrative embodiment, mounting head section 700 is mounted to firstexit channel wall 600, second exit channel wall 602, and thecorresponding portions of blower cover plate 500 and bottom wall 520 ofexhaust blower 416 using a friction fit though other mounting devicesand/or methods may be used in alternative embodiments. In theillustrative embodiment, mounting head section 700 is sized and shapedto fit over first exit channel wall 600, second exit channel wall 602,and the corresponding portions of blower cover plate 500 and bottom wall520 of exhaust blower 416. Slits 710 formed in sidewalls of mountinghead section 700 provide a flexible fit.

In the illustrative embodiment, the channel formed by first exit channelwall 600 and second exit channel wall 602 and the corresponding portionsof blower cover plate 500 and bottom wall 520 has a square orrectangular cross-section though the channel may have differentcross-sectional shapes including circular, elliptical, or otherpolygons. Mounting head section 700 also has a square or rectangularcross-section that fits over the channel though mounting head section700 may have different cross-sectional shapes including circular,elliptical, or other polygons. In the illustrative embodiment, mountinghead section 700 fits over an exterior of first exit channel wall 600and second exit channel wall 602 and the corresponding portions ofblower cover plate 500 and bottom wall 520 though in an alternativeembodiment, mounting head section 700 may fit within an interior offirst exit channel wall 600 and second exit channel wall 602 and thecorresponding portions of blower cover plate 500 and bottom wall 520.

Tapered body section 702 extends between mounting head section 700 andreducing body section 704. Tapered body section 702 has a squarecross-section where it joins with mounting head section 700 and acircular cross-section where it joins with reducing body section 704 toprovide a transition wall section between mounting head section 700 andreducing body section 704. Reducing body section 704 has a funnel shapewith curved walls that decrease in circumference toward expanding bodysection 800. The funnel shape of reducing body section 704 may havelinear or curved walls. Expanding body section 800 has a funnel shapethat increases in circumference from where expanding body section 800joins with reducing body section 704 to form a venturi tube portion ofnozzle duct 506. The funnel shape of expanding body section 800 may havelinear or curved walls. In alternative embodiments, mounting headsection 700, tapered body section 702, reducing body section 704, andexpanding body section 800 may have different cross-sectional shapesincluding circular, elliptical, or other polygons.

A plurality of snap fit fins 706 and a plurality of fins 708 are mountedto extend outward from an exterior surface of reducing body section 704.In the illustrative embodiment, the plurality of snap fit fins 706includes two snap fit fins located at 180-degree intervals aroundreducing body section 704. Each snap fit fin has a notch 707 in anexterior surface of the fin. In the illustrative embodiment, theplurality of fins 709 includes two fins located at 180-degree intervalsaround reducing body section 704. The plurality of snap fit fins 706 areseparated from the plurality of fins 708 by 90-degrees. In alternativeembodiments, nozzle duct 506 may include a greater or a fewer number ofthe plurality of snap fit fins 706 and/or the plurality of fins 708.

Referring to FIG. 9A, a back cross-sectional view of exhaust duct 314 isshown in accordance with an illustrative embodiment. Referring to FIG.9B, a left cross-sectional view of exhaust duct 314 is shown inaccordance with an illustrative embodiment. Referring to FIG. 9C, asecond left cross-sectional view of exhaust duct 314 is shown inaccordance with an illustrative embodiment. Referring to FIG. 10 , aback cross-sectional view of nozzle duct 506 is shown in accordance withan illustrative embodiment. Referring to FIG. 11 , a backcross-sectional view of cone duct 508 is shown in accordance with anillustrative embodiment.

Cone duct 508 is mounted to nozzle duct 506 by sliding cone section 712over expanding body section 800 and reducing body section 704 with a finof the plurality of fins 708 aligned with a fin slit of the plurality offin slits 718 and with a snap fit fin of the plurality of snap fit fins706 aligned with a snap fit slit of the plurality of snap fit slits 720.Cone duct 508 is slid over nozzle duct 506 until a wall portion ofreducing body section 712 between a snap ft slit of the plurality ofsnap fit slits 720 and a respective snap aperture wall of the pluralityof snap aperture walls 722 reaches notch 707 of a respective snap fitfin of the plurality of snap fit fins 706. Other mounting devices and/ormethods may be used in alternative embodiments.

In the illustrative embodiment, cone section 712 is sized to fit overreducing body section 704 while leaving an air gap between the firstduct wall of cone duct 508 and the second duct wall of nozzle duct 506.The mating of the snap fit features ensures a proper alignment to formthe air gap and limits a distance that nozzle duct 506 is inserted intocone duct 508. In the illustrative embodiment, nozzle duct 506 and coneduct 508 are formed of two distinct objects that are mounted to eachother. In alternative embodiments, nozzle duct 506 and cone duct 508could form exhaust duct 314 with a greater or a fewer number of distinctelements.

The air gap varies in width between an interior surface of cone section712 and an exterior surface of expanding body section 800 and reducingbody section 704. For example, referring to FIG. 9B, a first air gapwidth 900 is shown between the exterior surface of expanding bodysection 800 and the interior surface of cone section 712. Referring toFIG. 9C, a second air gap width 902 is shown between the exteriorsurface of reducing body section 704 and the interior surface of conesection 712. The air gap supports entry of ambient air between theinterior surface of cone section 712 and the exterior surface ofexpanding body section 800 and reducing body section 704. The ambientair is exterior of the enclosed space that receives the drying exhaustair.

Exhaust system 124 pulls hot humid air from wash tub 200 into air intakehead 126 where it travels through intake conduit 130 and into the sealedspace between outer exhaust wall 128 and inner exhaust wall 402. Track404 guides liquid toward drain 406 and air toward blower fan 318.Ambient air may be added to the sealed space through first air intakeaperture wall 408 and second air intake aperture wall 410. The dryingexhaust air received into blower fan 318 is received into mounting headsection 700 and/or tapered body section 702 of nozzle duct 506. Thepressure change that results from the venturi effect of nozzle duct 506pulls warmer dryer ambient air into cone section 712 from a basestructure of dishwasher 100 below tub bottom wall 202 and above bottomwall 114 as shown in FIG. 3B. The warmer dryer ambient air mixes withthe hot humid drying exhaust air to lower the humidity and temperatureof the drying exhaust air that exits spout section 716 of cone duct 508eliminating condensation on kickplate 132, door 102, the floor in frontof dishwasher 100, and any surrounding surfaces such as cabinetry.

Exhaust duct 314 lowers a humidity of drying exhaust air by using theventuri effect to draw in and mix ambient air with the hot humid dryingair from an interior of dishwasher 100 during the drying cycle. Exhaustduct 314 lowers the humidity of drying exhaust air without using anyadditional fans or moving parts. Use of exhaust duct 314 may furtherincrease a drying speed by allowing exhaust system 124 to pull higherrelative humidity air from wash tub 200 while providing less ambient airon an inlet side of exhaust system 124 (prior to entry into blower fan318) thereby providing a greater volume flow rate through the entiresystem and reducing an amount of time for the drying cycle. For example,exhaust duct 314 may reduce or eliminate the need for ambient air beingpulled through first air intake aperture wall 408 and/or second airintake aperture wall 410 and into the sealed space.

Referring to FIG. 12 , an air flow velocity through exhaust duct 314 isshown in accordance with an illustrative embodiment. Referring to FIG.13 , a water vapor fraction in exhaust duct 314 is shown in accordancewith an illustrative embodiment. The air flow velocity and water vaporfraction were computed using computational fluid dynamics of theillustrative exhaust duct 314. The structural dimensions of theillustrative exhaust duct 314 were selected using computational fluiddynamics. Nozzle duct 506 creates a venturi tube effect that increasesthe velocity of the air as it flows through exhaust duct 314. Incomparison with an existing exhaust duct, exhaust duct 314 reduced therelative humidity of the exhaust air by ˜15%. Testing of dishwasher 100with exhaust duct 314 mounted in a variety of environments includingwith a long outer door panel and a high kickplate 132 showed nocondensation on the outer door panel, floor, or adjacent cabinetry atany point during the drying cycle.

In designing exhaust duct 314, the inlet air velocity may be establishedeither as a predefined parameter or as part of a complete drying systemdesign. The cross-section for the inlet of ambient air may be a uniformcircular cross-sectional area. An efficient inner contour of reducingbody section 704 may be created to increase the velocity of the airpassing into expanding body section 800 without introducing disturbancesor creating a significant pressure drop. A length of the transition areacan be adjusted along with an internal radii and cross-sectional area toachieve this goal. An outlet of expanding body section 800 may bedefined to maintain a velocity past the annular opening formed by conesection 712 and expanding body section 800 to create a pressuredifferential required to draw in the drier ambient air. A ratio of thearea between the outlet of cone section 712 and of expanding bodysection 800 may be adjusted to maximize the velocity of the drierambient air. An annular gap formed between cone section 712 and taperedbody section 702 may be adjusted to ensure sufficient area exists toprevent unwanted pressure drop at this opening. Due to the contour oftapered body section 702, a length of cone section 712 can be altered toadjust this gap. A smooth transition in center section 714 may bedefined to complete the mixing of the humid and drier air. The shape ofspout section 716 is unimportant if the mixing is complete beforeentering that region.

The components of exhaust system 124 may be formed of one or morematerials, such as metal, glass, and/or plastic having a sufficientstrength and rigidity to provide the illustrated and/or describedfunction of exhausting drying exhaust air for numerous drying cycles.

The word “illustrative” is used herein to mean serving as an example,instance, or illustration. Any aspect or design described herein as“illustrative” is not necessarily to be construed as preferred oradvantageous over other aspects or designs. Further, for the purposes ofthis disclosure and unless otherwise specified, “a” or “an” means “oneor more”. Still further, in the detailed description, the use of “and”or “or” is intended to include “and/or” unless specifically indicatedotherwise.

The foregoing description of illustrative embodiments has been presentedfor purposes of illustration and of description. It is not intended tobe exhaustive or to limit the subject matter to the precise formdisclosed. Modifications and variations are possible in light of theabove teachings or may be acquired from practice of the disclosedsubject matter. The embodiments were chosen and described in order toexplain the principles of the disclosed subject matter and as practicalapplications of the disclosed subject matter to enable one skilled inthe art to utilize the disclosed subject matter in various embodimentsand with various modifications as suited to the particular usecontemplated.

What is claimed is:
 1. An exhaust duct comprising: a nozzle ductcomprising a first wall that forms a first aperture, wherein the firstwall includes a reducing section comprising a first edge and a secondedge opposite the first edge; and an expanding section mounted to thereducing section, the expanding section comprising a third edge and afourth edge opposite the third edge, wherein the reducing section has acircumference that decreases from the first edge to the second edge,wherein the second edge is mounted to the third edge of the expandingsection, wherein the expanding section has a circumference thatincreases from the third edge to the fourth edge; and a cone duct, thecone duct comprising a second wall that forms a second aperture, whereinthe nozzle duct is mounted within at least a portion of the secondaperture, wherein an air gap is provided between at least a portion ofan interior of the second wall and at least a portion of an exterior ofthe nozzle duct to allow air to enter the second aperture.
 2. Theexhaust duct of claim 1, wherein the cone duct has a circumference thatdecreases from a fifth edge to a sixth edge that is opposite the fifthedge, wherein the nozzle duct is inserted within the fifth edge.
 3. Theexhaust duct of claim 1, wherein the cone duct comprises a cone sectionwith a circumference that decreases from a fifth edge to a sixth edgethat is opposite the fifth edge, wherein the nozzle duct is insertedwithin the fifth edge.
 4. The exhaust duct of claim 3, wherein the coneduct further comprises a spout section comprising a bottom wall portion,a top wall portion, and sidewall portions mounted between the bottomwall portion and the top wall portion, wherein the spout section extendsfrom the sixth edge of the cone section.
 5. The exhaust duct of claim 4,wherein the bottom wall portion extends further from the sixth edge thanthe top wall portion.
 6. The exhaust duct of claim 3, wherein the coneduct further comprises: a spout section comprising a bottom wallportion, a top wall portion, and sidewall portions, a seventh edge thatcomprises an edge of the bottom wall portion, the top wall portion, andthe sidewall portions and an eighth edge opposite the seventh edge; anda center section comprising a ninth edge and a tenth edge opposite theninth edge, wherein the ninth edge of the center section is mounted tothe sixth edge of the cone section and the tenth edge of the centersection is mounted to the seventh edge of the spout section, wherein thebottom wall portion of the spout section extends further from the tenthedge than the top wall portion.
 7. The exhaust duct of claim 6, whereinthe center section has a funnel shape.
 8. The exhaust duct of claim 7,wherein the center section has a circumference that increases from theninth edge to the tenth edge.
 9. The exhaust duct of claim 8, whereinthe ninth edge of the center section has a circular shapedcircumference, and the tenth edge of the center section has a polygonalshaped circumference.
 10. The exhaust duct of claim 3, wherein the conesection has a funnel shape.
 11. The exhaust duct of claim 1, wherein theexpanding section has a funnel shape.
 12. The exhaust duct of claim 11,wherein the funnel has linearly sloped walls.
 13. The exhaust duct ofclaim 11, wherein the funnel has curved walls.
 14. The exhaust duct ofclaim 1, wherein the reducing section has a funnel shape.
 15. Theexhaust duct of claim 14, wherein the funnel has linearly sloped walls.16. The exhaust duct of claim 14, wherein the funnel has curved walls.17. The exhaust duct of claim 1, wherein the nozzle duct is configuredto mount to an exhaust channel of an exhaust blower closer to the firstedge of the reducing section than to the second edge of the reducingsection.
 18. The exhaust duct of claim 1, wherein the nozzle duct andthe cone duct are individual ducts that are fastened to each other. 19.An exhaust system comprising: an exhaust blower comprising an exhaustchannel; and an exhaust fan mounted within the exhaust channel to movereceived air into the exhaust channel when the exhaust fan is on; and anexhaust duct comprising a nozzle duct comprising a first wall that formsa first aperture, wherein the first wall includes a reducing sectioncomprising a first edge and a second edge opposite the first edge; andan expanding section mounted to the reducing section, the expandingsection comprising a third edge and a fourth edge opposite the thirdedge, wherein the reducing section has a circumference that decreasesfrom the first edge to the second edge, wherein the second edge ismounted to the third edge of the expanding section, wherein theexpanding section has a circumference that increases from the third edgeto the fourth edge, wherein the nozzle duct is mounted to the exhaustchannel of the exhaust blower with the first edge of the reducingsection closer to the exhaust channel than the second edge of thereducing section; and a cone duct, the cone duct comprising a secondwall that forms a second aperture, wherein the nozzle duct is mountedwithin at least a portion of the second aperture, wherein an air gap isprovided between at least a portion of an interior of the second walland at least a portion of an exterior of the nozzle duct to allow air toenter the second aperture.
 20. A dishwasher comprising: a body; aconduit system configured to provide washing fluid to an interior of thebody; and an exhaust system mounted to the body, the exhaust systemcomprising an intake conduit connected to receive air from the interiorof the body during a drying cycle of the dishwasher; an exhaust blower,the exhaust blower comprising an exhaust channel; and an exhaust fanmounted within the exhaust channel to receive the air received into theintake conduit and to move the received air into the exhaust channelwhen the exhaust fan is on; and an exhaust duct comprising a nozzle ductcomprising a first wall that forms a first aperture, wherein the firstwall includes a reducing section comprising a first edge and a secondedge opposite the first edge; and an expanding section mounted to thereducing section, the expanding section comprising a third edge and afourth edge opposite the third edge, wherein the reducing section has acircumference that decreases from the first edge to the second edge,wherein the second edge is mounted to the third edge of the expandingsection, wherein the expanding section has a circumference thatincreases from the third edge to the fourth edge, wherein the nozzleduct is mounted to the exhaust channel of the exhaust blower with thefirst edge of the reducing section closer to the exhaust channel thanthe second edge of the reducing section; and a cone duct, the cone ductcomprising a second wall that forms a second aperture, wherein thenozzle duct is mounted within at least a portion of the second aperture,wherein an air gap is provided between at least a portion of an interiorof the second wall and at least a portion of an exterior of the nozzleduct to allow air to enter the second aperture.